chromium/third_party/blink/web_tests/external/wpt/css/css-transitions/transition-property-019-manual.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Transitions Test: transition-property - font-size</title>
<link rel="author" title="Intel" href="http://www.intel.com">
<link rel="author" title="Shiyou Tan" href="mailto:[email protected]">
<link rel="help" href="https://drafts.csswg.org/web-animations-1/#animation-type">
<link rel="help" href="https://drafts.csswg.org/css-fonts-3/#font-size-prop">
<meta name="assert" content="Test checks that the 'font-size' property is animatable.">
<style>
  #test {
    font-size: 20px;
    transition-duration: 2s;
    transition-property: font-size;
    transition-timing-function: linear;
  }
</style>
<body>
  <p>Click the 'FillerText' below. Test passes if the size of 'FillerText' increases gradually not immediately until it stops.</p>
  <div id="test">
    FillerTextFillerTextFillerTextFillerText
  </div>
  <script>
    (function() {
      var test = document.querySelector("#test");
      test.addEventListener("click", function(evt) {
        test.setAttribute("style", "font-size: 40px;");
      }, false);
    })();
  </script>
</body>